The use of Hall generators for the measurement of magnetic induction has found increasing importance in recent years. They may be utilized for the measurements of magnetic fields, e.g. in high energy particle accelerators, whereever magnetic fields are generated for control or instrumentation purposes and even for feedback control of magnetic fields. Hall generators, as is known, have a drive-current path and, at right angles thereto, an output-voltage path across which the Hall voltage is generated. A magnetic field is applied perpendicularly to both of these paths.
Because of the negative-temperature coefficient of the Hall voltage, a Hall generator, unless provided with a temperature-compensation circuit, will shown an undesired temperature drift. In the SIEMENS databook 1976/77 Magnetfeldabhangige Halbleiter (Magnet Field Dependent Semiconductors), a circuit for compensation purposes is disclosed.
In this circuit the compensation for the temperature drift of the Hall voltage is effected in a bridge circuit in which the Hall generator forms an arm of the bridge. Apart from the well known disadvantages of such bridge circuits with the coupling-in of the voltage generated by the drive current and the tuning out of the signal voltage (Hall voltage), this temperature-compensation circuit has the disadvantage that it is unable to suppress other temperature- and amplitude-dependent perturbations, noise or interference polarities.